I. Field of the Invention
The present invention relates to both a system and method for assessing road tolls on vehicles as a function of the fuel efficiency of the vehicle.
II. Description of Related Art
There are many toll roads in the United States and elsewhere and most of these use a fixed price for tolling based on the vehicle type. For example, a two axle passenger car will typically have a lower toll rate than a small commercial vehicle or a large commercial vehicle.
In order to assess a toll, many jurisdictions use electronic toll collection which is widely implemented in the United States. The system includes a tag which is attached to the vehicle windshield and which contains information relative to an account or person associated with the tag. The tag itself is self-contained thus having a battery as well as wireless communication capability. The tag does not, however, communicate with the vehicle electronic systems.
As the vehicle with the tag is driven past a tag reader at a toll station, the toll station reads the account information from the tag and then, by accessing stored data associated with that tag account number, assesses the proper toll to an account associated with the tag.
One shortcoming of these previously known electronic toll systems and the vehicle tags is that it is not possible for the toll station to identify when a tag for one type of vehicle is transferred to a different type of vehicle for which a different road toll may apply. For example, if a tag for a passenger car which enjoyed a relatively low road toll were transferred to a heavy duty truck, the heavy duty truck would be recognized by the toll reader as the passenger car and assessed a lower toll rate.
A still further disadvantage of these previously known electronic toll collection systems is that it has previously been impossible for the toll station to vary the toll rate as a function of fuel efficiency and/or fuel economy, which is directly related to the emission of carbon dioxide. However, it would be highly desirable to reward fuel efficient vehicles and thus low carbon dioxide emission as well as fuel efficient driving habits with lower road tolls.